Method of making a flanged hub by casting and coining



Nov. 29, 1966 R, ILCOX ENETAL 3,287,797

METHOD OF MAKING A FLANGED HUB BY CASTING AND COINING Filed March 30, 1964 4 Sheets-Sheet 1 FIG. I

:7 2 RAYMOND J. WILCOX i A fi r P. 1 Sca-awmzsgg WARREN L. MEYER ATTORNEYS NOV. 29, 1966 J WILCQX ET AL METHOD OF MAKING A FLANGED HUB BY CASTING AND COINING Filed March 30, 1964 4 Sheet-Sheet 2 raa RAYMOND J. WlLC% Z B ERT P SCHgEIZER a WARREN L. MEYER 'Flc. 5

ATTORN E Y5- Nov. 29, 1966 I R. J- WlLCOX ETAL 3,287,797

METHOD OF MAKING A FLANGED HUB BY CASTING AND COINING Filed March 30, 1964 4 Sheets-Sheet 5 ffi. i l

RAYMOND J. Wu.cox EBB PEQ E. SCHWEIZER e; WARREN L. MEYER -mmmm ATTORNEYS FIG. 7

NOV. 29, 1966 J, w cox ET AL 3,287,797

METHOD OF MAKING A FLANGED HUB BY CASTING AND COINING Filed March 30, 1964 4 Sheet-Sheet 4 1 K Fm. H

RAYMOND J. WILCOX %?58? P. SQHWE|2 e WARREN L. MEYER ATTORNEYS United States Patent 3,287,797 METHOD OF MAKING A FLAN GED HUB BY I CASTING AND COINING Raymond J. Wilcox, Albert P. Schweizer, and Warren L. Meyer, Lansing, Mich, assignors to Motor Wheel Corporation, Akron, Ohio, a corporation of Ohio Filed Mar. 30, 1964, Ser. No. 355,743 10 Claims. (Cl. 29--159.3)

This invention relates to a flanged hub and in particular to the method of making a flanged hub by casting and 3,287,797 Patented Nov. 29, 1966 outer surface 30 recessed from an adjacent face 32 of flange 14, including an area 34 immediately adjacent the radially outer tip of each rib 20.

In a finished hub, face 32 must be flat and true with respect to bores 16, 18 after they are machined, to accurately position a brake drum back which is later assembled on face 32. Face 32 must also be flat and true with respect to ribs 20 which position the hub for accurate machining of bores 16, 18 and also position and center the drum back when it is assembled on the finished hub. After blank 10 has been cast and cooled, face 32 and ribs 20 are accurately shaped by a coining operation which is performed on a press (FIG. having a conventional bed (not shown) and an opposed vertically movable head (not shown). The bed and head each have a die shoe 36, 38 on which a lower annular die 40 and an upper method for making flanged hubs by casting and coining operations that satisfy the above requirements.

In the drawings:

FIG. 1 is an end view of a flanged hub blank as it appears after casting but before coining.

FIG. 2 is a fragmentary longitudinal section taken along the line 2-2 of FIG. 1.

FIG. 3 is an enlarged section of a bolt hole boss taken along the line 33 of FIG. 1.

FIG. 4 is an enlarged section of a spoke taken along the line 44 of FIG. 1.

FIG. 5 is a fragmentary view of a coining press in its open position with the cast hub positioned therein.

FIG. 6 is a fragmentary view of the bottom face of an upper coining die in the press shown in FIG. 5.

FIG. 7 is a fragmentary vertical section taken along the line 77 of FIG. 6.

FIG. 8 is a fragmentary vertical section taken through a set of dies in the press to illustrate a shaving operation performed by the dies. In FIGS. 8, 9, and 11 the cross section of the hub corresponds generally to a cross section along line AA in FIG. 1.

FIG. 9 is a fragmentary vertical section taken through the dies to illustrate the coining operation performed on the flange of the hub.

FIG. 10 is an enlarged fragmentary section taken generally through a spoke in the left hand portion ofthe flange shown in FIG. 9 to illustrate dimension changes produced by shaving and coining operations.

FIG. 11 is an enlarged fragmentary section taken through a web of the right hand portion of the flange shown in FIG. 9 to illustrate dimension changes produced by shaving and coining operations.

A hub blank 10 (FIGS. 1-5) is formed of malleable cast iron by conventional casting techniques to the approximate dimensions of the finished hub. Hub blank 10 comprises a generally cylindrical body portion 12 having an axial bore 13, a flange 14 extending radially from body portion 12, and a plurality of circumferentially spaced ribs that extend radially of body portion 12. A pair of bearing cup bores 16 and 18 are located adjacent respective ends of bore 13. Flange 14, which is cast integrally with body portion 12, has an annular peripheral rim 22, a plurality of circumferentially spaced spokes 24 extending radially between body portion 12 and rim 22, and a tapered web 26 extending between spokes 24, rim 22 and body portion 12. A gate used in pouring the casting forms a gate pad 28 that replaces three of the spokes. Four of the spokes have enlarged bolt hole bosses 29 which along with gate pad 28 are pierced after the coining operation to form bolt holes. Web 26 tapers inwardly in a direction radially of flange 14 and has an annular die 42, respectively, are mounted. A stripper 43 on the head ejects blank 10 after the coining operation. Die 40 has a flat coining face 44 that is slightly concave, inclined upward as viewed in FIG. 5 toward its outer periphery at two and one-quarter degrees. An inner peripheral corner 46 on lower die 40 is rounded to center blank 10 in the press and also slightly cold work that portion of flange 14 adjacent body portion 12. Die 42 has a flat coining face 48 which is slightly convex, inclined upwardly from the central aperture toward the outer periphery at one-quarter degree, and a downward projecting peripheral flange 50 arranged to bottom on lower die 40. Die 42 has five longitudinal grooves 52 equally spaced circumferentially about its central bore 53 and an integral, generally rectangular, boss 56 immediately adjacent the lower end of each groove. Each boss has a radial inner surfaces 58 registering with the bottom of grooves 52 and a sharp inner corner 60. Intermediate grooves 52 the juncture of face 48 and bore 53 is formed with a slightly rounded corner 62.

Blank 10 is initially positioned in the open press with face 32 facing upward and is centered by corner 46. When the head moves downward, corner 60 of die 42 contacts the crest of ribs 20 and continued downward movement of die 42 shaves the crest of ribs 20 (FIG. 8) so that the shaved crests of ribs 20 define a precisely dimensioned circumference. After die 42 bottoms on flange 14 continued downward movement of die 42 coins both faces of flange 14 until flange 50 bottoms on die 42. FIG. 9 illustratesthe coining operation when die 42 has reached its lower limit of vertical travel. The one-quarter degree taper in coining faces 44, 4S compensate for spring back of flange 14 that occurs after the coining operation is completed. The net two degrees taper between coining faces 44, 48- causes severe coining at the outer periphery of flange 14 with the coining becoming less severe radially inward on the flange. Therefore, annular rirn 22, bolt bosses 29 and gate pad 28, being located near the outer periphery of flange 14, receive severe coining while the area of the flange near body portion 12 receives little or no coining. Additionally, the taper in coining faces 44, 48 causes the material of flange 14 to flow radially inward during the coining operation. To complete the coining operation, die 42 is raised and blank 10 is ejected from die 42 by stripper 43.

In FIG. 3 the coined shape of the bolt hole bosses 29 is illustrated by broken line 64 and in FIG. 4 the coined shape of spokes 24 is illustrated by broken line 66. The coined thickness of rim 22 is illustrated by broken line 68 in FIGS. 3 and 4. Since face 48 of die 42 extends radially inward past the outer tip of ribs 20, face 32 of flange 14 is coined flat inwardly of the ribs 20 as illustrated in FIG. 1 by the broken line 69. which corresponds to the configuration of grooves 52, bore 53, and surface 58 of die 42. In the enlarged sectional views shown in FIG. 10 which is taken through one of the spokes 24 and FIG. 11 which is taken through web 26, the coined thickness of flange 14 is shown in full lines while the contour of the flange before being coined is illustrated by broken lines 70. A fillet 71 formed by corner 62 on die 42 minimizes stress at the juncture of flange 14 and body portion 12. The shaved dimension of ribs 20 is shown in full lines while the corresponding contour of ribs 20 before shaving is illustrated by broken line 72. As illustrated by a bur 74, metal shaved from the crest of ribs 20 by corner 60 has been pushed into recessed areas 34. Boss 56, projecting below face 48, assures that bur 74 will be below face 32 and will not interfere with assembling a drum back against face 32. Waviness in the coined surfaces of the flange faces is minimized because metal from rim 22, spokes 24, gate pad 28 and bosses 29 is free to flow toward recessed surface 30. In the various figures the amount of material displaced from the crests of ribs 20 by shaving and the extent of dimension change produced by coining are greatly exaggerated for purposes of illustration. To assure accurate coining, the dimensions of the cast hub should conform quite closely to the dimensions of the finished hub. By way of example, for a typical automobile wheel hub, a thickness in the order of 0.030 of an inch is shaved from each rib 20 and the total change in flange thickness is in the order of 0.030 of an inch.

When a flanged hub is cast and then coined as hereinbefore described, face 32 is flat and true with respect to a circumference defined by the shaved surfaces of ribs 20. Bearing cup bores 16, 18 may then be machined concentrically within narrow tolerances with respect to the circumference defined by ribs 20, and the faces of flange 14 will be accurately located with. respect to the axis of the machined bearing cup bores.

We claim:

1. In the method of making a flanged hub, the steps of casting a blank of malleable cast iron to form a generally cylindrical body portion having a radial flange, said flange having an annular peripheral rim, a plurality of radially extending spokes, and depressions in the spacing between said spokes, said rim and said body portion, and then cold working radial faces of said rim and said spokes within an annular zone extending radially inward from said rim with a pair of opposed dies to flow material from said rim and said spokes into said depressions.

2. In the method of making a flanged hub, the steps of casting a blank of malleable cast iron to form a generally cylindrical body portion having a radial flange and a plurality of circumferentially spaced, axial ribs, said ribs terminating adjacent one face of said flange, said flange having an annular outer peripheral rim and a plurality of circumferentially spaced, radial spokes integral with said rim and said body portion, shaving the crests of said ribs to provide an accurately dimensioned circumference defined by said shaved crests, and coining radial faces of said annular rim and said spokes within an annular zone extending radially inward from said rim with opposed flat-faced dies to provide a flange having a flat face within said zone.

3. The method set forth in claim 2 further comprising the step of machining terminal portions of a central longitudinal bore in said hub with said hub being accurately positioned by said shaved crests of said ribs while said terminal portions are machined.

4. The method set forth in claim 2 wherein said ribs are shaved and said flange is coined in a substantially Continuous operation.

5. The method set forth in claim 4 wherein said shaving and coining are performed by an annular die having a flat leading face for coining one face of said flange, and means at the juncture of said face and the bore of said annular die for shaving the crests of said ribs.

6. The method set forth in claim 4 wherein said shaving and coining are performed by an annular die having a flat leading face and a plurality of longitudinal grooves arranged to register with said ribs, said face having a plurality of outwardly projecting bosses thereon adjacent said grooves, each of said bosses having a sharp corner edge thereon for shaving the crests of said ribs.

7. In the method of making a hub having a flange with a radial face on the flange that is fiat within predetermined tolerances throughout an annular zone extending radially inwardly from the outer periphery of the flange, the steps of casting a' blank of malleable cast iron to form a generally cylindrical body portion having a radial flange with a radial face and then cold working said blank by coining the radial face on said blank flange within the annular zone extending radially inwardly from the outer periphery of the blank flange to bring the face flat within said predetermined tolerances throughout the annular zone of the finished hub.

8. The method set forth in claim 7 wherein said blank is cold worked severely at the outer periphery of the blank flange and substantially simultaneously cold Worked less severely radially inwardly of the outer periphery of the blank flange with opposed coining dies having inclined flat faces.

9. The method set forth in claim '7 wherein said cylindrical body portion of the blank is cold worked with a die and then the radial face on the flange is cold worked by said die so that the radial face is true with respect to the body portion that was cold worked.

10. In the method of making a flanged hub, the steps of casting a blank of malleable cast iron to form a generally cylindrical body portion having a radial flange, said flange having an annular peripheral rim and a pluurality of radially extending spokes integral with said rim and said body portion and then cold Working said flange by coining a radial face of said annular rim and said spokes within an annular zone extending radially inwardly from said rim with opposed coining dies having inclined flat faces to cause severe coining adjacent the outer periphery of said flange with the coining becoming less severe radially inwardly of said outer periphery.

References Cited by the Examiner UNITED STATES PATENTS 736,551 8/1903 Roemer 29-159 1,149,267 8/1915 Keithley 29-168 1,428,219 9/1922 Crawford 72-401 1,527,364 2/ 1925 Kinzel 72-45 1,736,495 11/1929 Graff 29-529 2,323,972 7/ 1943 Brauchler 29-528 2,492,967 1/ 1950 Clark 29-1593 2,587,864 3/1952 Lefere 29-1593 2,738,571 3/1956 Turnbull 29-528 XR 2,781,231 2/1957 Black 301- 2,812,216 11/1957 Hykes 301-105 2,972,183 2/1961 Greenshields et al. 29-1593 JOHN F. CAMPBELL, Primary Examiner.

ARTHUR L. LA POINT, WHIT MORE A. WILTZ,

THOMAS H. EAGER, Examiners.

R. I. JOHNSON, Assistant Examiner. 

1. IN THE METHOD OF MAKING A FLANGED HUB, THE STEPS OF CASTING A BLANK OF MALLEABLE CAST IRON TO FORM A GENERALLY CYLINDRICAL BODY PORTION HAVING A RADIAL FLANGE, SAID FLANGE HAVING AN ANNULAR PERIPHERAL RIM, A PLURALITY BETWEEN SAID SPOKES, SAID RIM AND SAID BODY PORTION, AND THEN COLD WORKING RADIAL FACES OF SAID RIM AND SAID SPOKES WITHIN AN ANNULAR ZONE EXTENDING RADIALLY INWARD FROM SAID RIM WITH A PAIR OF OPPOSED DIES TO FLOW MATERIAL FROM SAID RIM AND SAID SPOKES IN SAID DEPRESSIONS. 